Open Access
ASTRA 3B horn antenna design
(2010) Teniente Vallinas, Jorge; Río Bocio, Carlos del; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
The ASTRA 3B satellite includes 60 Ku-band state-of-the- art transponders and 4 Ka-band transponders. The spacecraft have been designed for the distribution of both direct-to-home (DTH) broadcast services and two way broadband services across Europe. After Astra 2B and Astra 1M, Astra 3B is the third Astra satellite to be built by ASTRIUM. Two different horn antennas, for Ku- and Ka-bands, were designed with very stringent requirements as it is usually required for space applications. For the horns the cross-polar levels should be below -45 dB, and the return loss below -30dB for all frequency bands. Normally the horn aperture is fixed by the required illumination of the reflector edges, so it is difficult to reduce the aperture size of a horn antenna. Nevertheless, thanks to the design technique used, the relation between the output aperture and the total horn length for the Ka-band was approximately 0.56 and for the Kuband was something like 0.76. This means that the lengths of the horn antennas are 1.8 and 1.32 times the respective apertures. Furthermore, the taper and the phase center movement inside the respective bandwidths could be controlled and limited to certain limits during the optimization procedure, obtaining a very efficient configuration when they were combined with the reflectors. The horn antennas were based on the combination of horizontal and vertical corrugations and they were designed by the Antenna group of the Public University of Navarra.
Open Access
New coplanar waveguide based on the gap waveguide technology
(IEEE, 2021) Biurrun Quel, Carlos; Teniente Vallinas, Jorge; Río Bocio, Carlos del; Institute of Smart Cities - ISC
A new planar waveguide, coined Inverted coplanar gap waveguide is presented. The concept of gap waveguides and parallel plate suppression between perfect magnetic and a perfect electric conductors is applied to coplanar waveguides in order to create a low-dispersion, low-loss transmission line. The combination of an artificial magnetic conductor and channelized top cover allow the propagation of an even coplanar mode with a strong component propagating over the air while solving encapsulation matters without the use of metallic vias. The main theory behind this new concept is presented and supported by FEM simulations on a commercial software package.
Open Access
Noise in coherently radiating periodic structures beam forming networks
(IEEE, 2022) Biurrun Quel, Carlos; Río Bocio, Carlos del; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Following the noise wave theory, beam forming networks based on Coherently Radiating Periodic Structures (CORPS-BFN) are analysed and proven to be capable of enhancing the Signal to Noise Ratio of the system by analogically multiplexing the signal and noise contributions present at every input port. The geometry of the network determines the maximum enhancement achievable, which is demonstrated to be independent from insertion losses. These findings are supported by a mathematical approach, as well as with experimental data.
Open Access
Multi-channel feedarray reflector antenna based radar concept for HRWS SAR imaging
(IEEE, 2021) Castillo, Javier del; Orgaz, Lara; García, Quiterio; Memeletzoglou, Nafsika; Toso, Giovanni; Imbembo, Ernesto; Biurrun Quel, Carlos; Río Bocio, Carlos del; Institute of Smart Cities - ISC
Large deployable reflector based multi-channel antenna systems are a key component of next generation SAR missions as they allow implementing multi-beam imaging capabilities and provide an efficient way to overcome the classical SAR resolution-coverage trade-off, covering wide swaths with high azimuth resolution. The presented work shows the design of a multichannel L-band SAR system and antenna architecture based on different feeders concepts and capable to map 400 km ground swath with 5 meter spatial resolution in dual polarization. The paper describes a preliminary design and architecture of the SAR system and the antenna where different design aspects including beamforming concepts and feedarray implementation techniques have been identified and assessed in view of achieving the required SAR performances while reducing the overall complexity of the solution.
Open Access
Low-profile conformal UWB antenna for UAV applications
(IEEE, 2019) Balderas, Luz I.; Reyna, Alberto; Panduro, Marco A.; Río Bocio, Carlos del; Gutierrez, Arnulfo R.; Institute of Smart Cities - ISC
This article presents a new design of an ultra-wideband conformal antenna for Unmanned Aerial Vehicle (UAV) applications. The antenna is a low-profile structure which is very suitable to diminish aerial vehicle drag problem. The design utilizes Rogers Duroid 5880LZ material with dimensions of 29 mm x 39 mm. The measurement results show an ultrawideband performance of the S-11 < -10dB from 2.9 GHz to 15.9 GHz. A Y-rounded shape achieves this frequency range with a parasitic circular element at the center of the structure. The acceptable radiation pattern performance is until 10.1 GHz, and the system fidelity factor is SFF > 0.9 in the maximum radiation. The proposed antenna was simulated and measured to test its performance when it is mounted on an UAV model.
Open Access
Synthesis of volumetric ring antenna array for terrestrial coverage pattern
(Hindawi, 2014) Reyna, Alberto; Panduro, Marco A.; Río Bocio, Carlos del; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
This paper presents a synthesis of a volumetric ring antenna array for a terrestrial coverage pattern. This synthesis regards the spacing among the rings on the planes X -Y, the positions of the rings on the plane X -Z, and uniform and concentric excitations. The optimization is carried out by implementing the particle swarm optimization. The synthesis is compared with previous designs by resulting with proper performance of this geometry to provide an accurate coverage to be applied in satellite applications with a maximum reduction of the antenna hardware as well as the side lobe level reduction.
Open Access
Design and characterization of terahertz CORPS beam forming networks
(Springer, 2023) Biurrun Quel, Carlos; Haddad, Thomas; Sievert, Benedikt; Kress, Robin; Weimann, Nils; Erni, Daniel; Rennings, Andreas; Stöhr, Andreas; Teniente Vallinas, Jorge; Río Bocio, Carlos del; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
This work reviews the design and applicability of beam-forming networks based on Coherently Radiating Periodic Structures (CORPS-BFN) at Terahertz (THz) frequency bands. These versatile networks offer two operation modes: a continuous beam steering – feeding an antenna array with a linearly progressive phase distribution – using a reduced number of phase controls; or a multi-beam operation, generating independent, overlapped beams. These networks are built upon the concatenation of power combiners/dividers (PCDs) with isolated outputs. The isolation is provided by monolithically integrated resistors, implemented with Ti/TiO thin films for the first time. In this work, a planar prototype of a (inputs/outputs) microstrip CORPS-BFN for operation in the WR3.4/WM-864 band (220–330 GHz) on a thin 50 m Indium Phosphide (InP) substrate is designed, fabricated, and characterized. The measured S-parameters show a reflection coefficient better than -15 dB and an insertion loss between 1.6 and 3.2 dB in the whole band. In addition, an isolation better than 20 dB between the input ports has been measured. An overall remarkable agreement is observed between the measurements and the simulations. Last, the applications, scalability and efficiency of this type of networks at the targeted band are discussed in detail.
Open Access
Design of concentric ring antenna arrays for isoflux radiation in GEO satellites
(Institute of Electronics, Information and Communication Engineers (IEICE), 2011) Reyna, Alberto; Panduro, Marco A.; Río Bocio, Carlos del; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
The design of concentric rings arrays for isoflux radiation is reported in this paper. This design considers the reduction of the side lobe level and the isoflux radiation requirements for Geostationary Earth Orbit (GEO) satellites. The optimization problem considers the spacing between rings and the levels of amplitude excitations. The well-known method of Particle Swarm Optimization (PSO) is utilized for the optimization. The obtained results could lead the satellite hardware to be reduced significantly even more than results presented previously in the literature.
Open Access
New hexagonal CORPS-BFN for multibeam antenna applications
(IEEE, 2020) Biurrun Quel, Carlos; Montesano, Antonio; Ederra Urzainqui, Íñigo; Iriarte Galarregui, Juan Carlos; Río Bocio, Carlos del; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
This work presents a new topology of a Coherently Radiating Periodic Structure - Beam Forming Network (CORPS-BFN) and its application for multibeam systems. A unit cell, consisting of a transition from a coaxial input to an intersection of three strip-lines with an angular span of 120 degrees, is proposed and analysed. A periodical replication of the cell gives rise to a uniform layer, allowing a proper matching of the ports of the network. Stacked layers allow in-phase propagation and distribution of the energy through the structure, increasing the number of output ports with each layer.
Open Access
Freehand system for antenna diagnosis based on amplitude-only data
(IEEE, 2021) Álvarez Narciandi, Guillermo; Laviada, Jaime; Álvarez López, Yuri; Ducournau, Guillaume; Luxe, Cyril; Belem Goncalves, Cybelle; Gianesello, Frederic; Nachabe, Nour; Río Bocio, Carlos del; Las-Heras, Fernando; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
This article presents a portable system for freehand antenna diagnosis and characterization based on amplitude-only data. The amplitude-only samples are acquired by moving a handheld probe, which is tracked by a motion capture system, in front of the antenna under test (AUT) aperture. The acquired measurements are processed using the phaseless sources reconstruction method to compute an equivalent current distribution on the AUT aperture. Finally, the radiation pattern of the AUT can be obtained by evaluating the corresponding radiation integrals. Unlike previous work, the use of amplitude-only data avoids the need of a phase reference, paving the way to the diagnosis and characterization of antennas under operational conditions. This fact, together with the handheld capabilities, makes the system very convenient for measurements of already deployed and onboard antennas. Moreover, these amplitude-only acquisitions also simplify the required hardware. The system has been validated through measurements in a wide frequency range from Ka-band up to 300 GHz. Despite that one cannot expect the same degree of accuracy that can be achieved under laboratory conditions (including an anechoic environment and highly accurate positioners), the system shows excellent capabilities to detect malfunctions, such as wrong amplitude/phase distributions, as well as a fair estimation of the far field.